taxonomy specific ' ' or 'or'

I was wondering if anyone could help me to alter the plugin code to filter results using ‘+’ or ‘,’ depending on which taxonomy is being filtered.

I found out how to change the files via this post
http://wordpress.org/support/topic/plugin-query-multiple-taxonomies-change-relation-from-and-to-or?replies=5.

but I was wondering if it would be possible to take this a stage further with a conditional statement like

[ Moderator Note: Please post code or markup snippets between backticks or use the code button. ]

if is_tax( "tax1" ){
$query[ $taxonomy ] = trim( implode( '+', $value ), '+' );
}else if is_tax( 'tax2' ) {
$query[ $taxonomy ] = trim( implode( ',', $value ), ',' );
}

would be possible.

any feedback would be great

tkhan

http://wordpress.org/extend/plugins/query-multiple-taxonomies/